1. Field of the Invention
This invention is directed to a progressively revealed display, and particularly to a structure where masks in front of the display are progressively moved to progressively reveal the display.
2. Description of the Prior Art
My previous U.S. Pat. No. 3,384,986, granted May 28, 1968, and entitled "Progressively Illuminated Sign" is directed to the concept of the progressive presentation of information. This prior patent teaches a useful and valuable structure. It calls for a belt shutter to be interposed between the light source and rows of information to be illuminated. The rows of information to be progressively illuminated must be either edge-lighted or back-lighted for progressive illumination by continuous belt motion, and thus this device is limited in application to displaying information which may be formed on transparent or translucent slats or sheets or on letter blocks. The sign of my prior patent is thus particularly adapted for use with removable letter means so that the information can be quickly and locally changed. However, it is limited by this arrangement of shutter controlled illumination of the letter means.